Getting ECU Trouble Code #9

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How do I troubleshoot an error code #9 ??

I have 95 LS/VTEC with an OBD1 ECU, distributor, etc. using a Conversion Harness adapter.

I am using a P28 chipped ECU which is looking for the Knock Sensor signal. This initially triggered a CEL code #23 which corresponds to Knock Sensor, but the car idled very erratically.

In checking it out a friend found out that the plugs were messed up - so we replaced them and the engine sounded much better and revved out pretty nicely.

But now the CEL #9.

What could cause this ??

Thanks for any help.


p28 ecu's don't have knock sensor circuitry. there's no way it can throw a code for it.

as for code 9, check your timing betwen your cam gears and crank pulley.